Foredom General Use Hand Piece 30 The #30 is the most popular hand piece. It features a geared 3-jaw #0 chuck that takes any size shank or drill bit up to 4mm. Comes with the CK-0 chuck key. Bench top tools such as the belt sander, hand piece holder & drill press are designed to accept the hand piece. Dimensions: length 5-3/16" x 1" diameter.